目前我正在尝试编写一个程序，它会返回一个列表，其中包含 booklooker.de 上书籍列表中最低价格的列表。该网站本身使用https，我想这就是问题所在。
代码：
import java.io.*;
import java.net.*;
import javax.net.ssl.HttpsURLConnection;
public class Booklooker {
public static void main(String[] args) throws Exception{
// TODO Auto-generated method stub
BufferedReader in = new BufferedReader(new FileReader("list.txt"));
PrintStream out = new PrintStream(new FileOutputStream(new File("result.txt")));
String book = "";
while((book = in.readLine()) != null){
book.replace(' ', '+').replace("ä", "%E4").replace("ö", "%F6").replace("ü", "%FC").replace("ß", "%DF");
URL link = new URL("https://secure.booklooker.de/app/result.php?sortOrder=preis_total&setMediaType=0&titel="+book);
HttpsURLConnection con = (HttpsURLConnection)link.openConnection();
BufferedReader site = new BufferedReader(new InputStreamReader(con.getInputStream()));
while(true){
String line = "";
if((line = site.readLine()) == null){
out.print("Error\n");
break;
}
else if(line.indexOf(" €") != -1){
int index = line.indexOf(" €");
double price = Double.parseDouble(line.substring(index-5, index).trim().replace(',', '.'));
index = line.indexOf(" €", index+12);
double postage = Double.parseDouble(line.substring(index-5, index).trim().replace(',', '.'));
out.print(price+postage+"\n");
break;
}
}
site.close();
}
in.close();
out.close();
System.out.println("Finished.");
}
}
并返回错误：
Exception in thread "main" java.io.IOException: Invalid Http response
at sun.net.www.protocol.http.HttpURLConnection.getInputStream(Unknown Source)
at sun.net.www.protocol.https.HttpsURLConnectionImpl.getInputStream(Unknown Source)
at Booklooker.main(Booklooker.java:16)
我不知道到底出了什么问题，但 HttpsURLConnection 似乎有问题。有人有想法吗？